At least three people were killed Friday when police in Cambodia opened fire on striking garment workers to break up a protest, police and human rights workers said.

Chuon Narin, deputy chief of the Phnom Penh Municipal Police, said officers fired AK-47 rifles after several hundred workers blocking a road south of the capital, Phnom Penh, began burning tires and throwing objects at the officers. In addition to the three who were killed, two people were wounded, he said. The incident followed another clash overnight.

Chuon Narin described the protesters as anarchists who were destroying public and private property. They were cleared from the street, at least temporarily, by early afternoon.

Chan Saveth, an observer from the human rights group Adhoc, said his group had tallied three dead and 10 hurt, seven apparently with gunshot wounds.

The violence comes at a time of political stress in the Southeast Asian nation. The opposition Cambodia National Rescue Party has demonstrated daily to demand that Prime Minister Hun Sen step down and call elections. Hun Sen, who has been in power since January 1985, was reelected in July, but opposition protesters accuse him of rigging the vote. He has rejected their demand.

Workers at most of the country’s more than 500 garment factories are on strike, demanding a doubling of the minimum wage, to $160 a month. The government has offered $100 a month.

Although the wage and election issues are not directly linked, the opposition has close ties to Cambodia’s labor movement. On Sunday, many workers joined a massive political rally organized by the opposition.

The workers represent a potent political force. The garment industry is Cambodia’s biggest export earner, employing about 500,000 people in clothing and shoe factories. In 2012, the country shipped more than $4 billion worth of products to the United States and Europe.

On Thursday, elite troops broke up a protest outside a factory in another area outside the capital, beating demonstrators and arresting 10 people, including Buddhist monks, according to witnesses from human rights groups.

In that case, according to the local human rights group Licadho, “The soldiers were seen brandishing metal pipes, knives, AK-47 rifles, slingshots and batons.”

The standoff over wages puts pressure on Hun Sen because increasing violence could drive the workers into a tighter alliance with the opposition, providing a vast pool of people for their increasingly confident street demonstrations. But the government is also close to the factory owners, whose export products drive the economy.

— Associated Press